A malware is a software designed to perform a malicious action against user's intention in a computer system. The malwares may include a computer virus, a worm, Trojan horse, spyware, a rootkit, and others. Recently, these malwares are exponentially increasing in numbers, and thus, it is getting ever more imperative to efficiently diagnose the malwares and prevent/repair damages therefrom.
In order to search for a file infected with a malware in a computer system and, if necessary, isolate or remove the infected file, an anti-virus program is generally installed in the computer system. If the anti-virus program is installed in the computer system, a malware inspection is usually performed for every file stored in a storage of the computer system. Also, if a portable storage such as a portable hard drive or a USB (Universal Serial Bus) drive is additionally connected to the computer system, the malware inspection is also performed for every file within the portable storage. However, a full inspection performed for every file in a mass storage may take a long time to complete.
Alternatively, the malware inspection may be selectively performed only on files with high possibility to be infected within particular system folders in which an operating system and application programs are installed. Such a selective inspection for the particular folders may be achieved in a shorter time period than that of the full inspection.
However, there may be some files infected with the malwares, but remain undetected if the malware inspection is made on the particular folders only. Moreover, even though the malware inspection is selectively performed only on the particular folders, current operating environment of the computer system renders that most of files within the particular folders may be candidate files to be subjected to the malware inspection to thereby make the reduction in the malware inspection time insignificant.